1. Field
This invention concerns unique structure for the gas exit port in the barrel of autoloading shotguns or the like, which port exits the high pressure firing gas into the gas cylinder of the spent shell ejection system. Such gun structure is shown and described in detail in U.S. Pat. Nos. 4,693,170; 4,487,103; 4,553,469 4,654,993; and 4,893,547, the disclosures of which are hereby incorporated herein by reference in their entireties.
2. Prior Art
The above patents show the conventional gas porting structure which, for example, is designated 68 in the aforesaid U.S. Pat. No. 4,693,170 patent. Such porting is simply a slot or holes drilled thru the barrel from the outside in which leaves burs or sharp edges on the inside of the barrel. These burs and edges will naturally collect shell debris from repeated firings and restrict the proper flow of gases and also clog the gas cylinder of the ejection system and other components of the gun.